Take-up mechanism for sewing-machines.



O. E. BROWN. TAKE-UP MECHANISM FOR SEWING MACHINES. APPLICATION FILED SEPT. 27, 1911.

1,097,389. Patented May 19, 19m

2 SHEETS-SHEET 1'.

III/ I I/IIIII/IIII/AHMZ WI T/VESSE S COLUMBIA PLANOGRAPH C0,, WASHINGTON, h. c.

0. E. BROWN. TAKE-UP MECHANISM FOR SEWING MACHINES. APPLIOATION FILED SEPT. 27, 1911.

1,097,389. Patented May 19, 191a WITNESSES.

- B y ATTORNEY UNlTED STATES PATENT OFFICE.

OTIS E. BROWN, OF BROCKTON, MASSACHUSETTS, ASSIGNOR TO THE SINGER MANU- FACTURING COMPANY, A CORPORATION OF NEW' JERSEY.

TAKE-UP MECHANISM FOR SEWING-MACHINES.

Application filed September 27, 1911.

To all whom-i1; may concern Be it known that I, Gris E. BROWN, a citizen of the United States, residing at Broclzton, in the county of Plymouth and State of h lassachusetts, have invented certain new and useful Improvements in Take- Up lvfechanisms for Sewing-lVlachines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to means for drawing up the thread and setting the stitches in sewing machines designed more particularly for stitching with waxed threads; and it has for its object to provide effective means for drawing up the slack needlethread in such manner as to produce a minimum liability to breakage while insuring the uniform setting of the stitches.

In its preferable form, the improvement comprises aroclr-lever fulcrumed upon the bracket-arm and provided with actuating means, and a vibratory take up lever connected with said rock-lever by a link whose points of connection with the same are carried into substantial alinement with the fulcrum of the rock-lever by the operative movements of the latter so as to produce a toggle-action upon the take-up lever as it approaches stitch-setting position to insure the utmost precision of action of the latter and a greatly retarded movement thereof in producing its greatest strain upon the thread. A thread-brake is preferably provided having one of its members automatically controlled by an operative connection with the take-up lever whereby the thread is released when the talte-up is in slack-producing position but is allowed to nip the thread while the take-up is performing its thread-drawing action. Means, including a toggle device connected with the presserfoot lifter, are provided for normally maintaining the other member of the thread brake stationary but adapted to retract the same to open the thread-brake when the machine is at rest.

In the accompanying drawings, Figure 1 's a sectional side elevation of a wax-thread sewing machine constructed in accordance with my application Serial No. (351,556 filed simultaneously herewith and emboc ying the present improvement. Fig. 2 is a sectional rear-side elevation, upon a larger scale, of the forward portion of the bracket- Specifieation of Letters Patent.

Patented May 19, 1914.

Serial No. 651,554.

arm, and Fig. 3 a bottom view of the same, and showing the mechanism of the present improvement in a different position from that represented in Fig. 1. Fig. l is a perspective view of the take-up lever, and Fig. 5 is a similar view of the thread-brake mechanism. Fig. 6 is an elevation partly in section of a portion of the threacbbrake. Fig. 7 is a transverse section through the split hub of the take-up lever and representing its bushing in elevation. Fig. 8 is a seetional elevation of the take-up lever and thread-brake in thread-slackening position.

As shown in the drawings, the frame of the machine comprises the hollow-base 1, tubular standard 2 and hollow overhanging arm 3 formed with the hollow head 4t. Journaled in the tubular arm 3 is the main shaft 5 having fixed thereon the needle-a0 tuating eccentric 6 operatively connected with the needle-bar 7 journaled in the jogging frame 8 and carrying the opencyed needle 9 to which the upper thread a is delivered by means of the reciprocating threadarm 10 and the vibratory thread-measuring arm 11. Cooperating with the needle beneath the work-plate 12 the loop-taker 13 which in the present machine is in the form of a rotary shuttle carrying a lower thread and receiving two rotations for each reciprocation of the needle.

The main-shaft 5 has secured thereon by means of the set-screw 1-11 the cam-cylinder 15 formed with the cam-groove 16 which is entered by the roller-stud 17 sustained by the upwardly extending arm 18 of a transverse roclr-lever whose hub 19 is fulcrumed upon the center-screws 20. The rock-lever is provided with a forwardly and downwardly extending arm 21 carrying the screw-stud 22 which is embraced by the apertured upper extremity of the link 23 whose apertured lower extremity embraces the screw-stud 24; secured by means of the clamp-screw 25 in the split boss 26 of the rearward arm 27 of the vibratory take-up lever having a forwardly extending arm 28 and an intermediate split hub 29. Adjustably secured within the hub 29 by means of the clamp-screw 29* is the bushing 30 titted loosely upon the transverse rocleshaft 31 which is mounted in bearing bosses 32 of the bracket-arm 3. The actuating cam-groove 16, as represented in Fig. 2, has a gradual curvature adjacent the stitch-setting portion, and the link 23 is so related to the members 21 and 27 that its pivotal connec tions with the same assume positions in substantial alinement with the fulcrum 20 of the rocklever when the latter is in extreme stitch-setting position represented in said figure, so that the take-up lever is caused to approach its extreme upper stitch-setting position very slowly to produce a corresponding gradual pull upon the thread in its final action thereon. The arm 28 of the take-up lever carries the transverse pivotal pins 33 spaced apart lengthwise thereof and upon which are mounted the grooved threadwheels 34 and 35 each embraced by a threadguard 36.

One end of the bushing 30 extends beyond the hub 29 and is provided with a lateral stop-shoulder 37 for engagement with a lateral pin 38 upon the hub 39 of the threadbrake lever 40 also loosely mounted upon the rockshaft 31 and carrying at its outer end the screw-pin ll sustaining the grooved thread-wheel a2 embraced by the shield 43. The thread-wheel 42 is disposed upon the lever 40 intermediate the circular paths of movement of the wheels 34 and 35 of the take-up lever.

The thread-brake lever a0 has an extension 40* rearward of the supporting shaft 31 which carries the screw-stud 4a sustaining the grooved thread-wheel 45 constituting the movable thread-engaging member of the thread-brake which is movable in the operation of the machine toward and from the normally stationary thread-brake member afforded by the segmental operative edge portion 46 of the plate 47 secured by means of the screw l8 upon a rigid arm 49 which is in turn secured by screws 50 upon the collar 51 fixed upon the transverse rock-shaft 31. The rock-shaft 31 has fixed upon its rearward end the hub 52 of a crank-arm 53 within whose forked outer end is pivoted by means of the pin 5% the lower end of a link 55 connected by the pin 56 with a swinging lever 57 mounted upon the fixed fulcrumstud 58. The lever 57 has a lateral arm 57 X pivotally connected by means of the pin 59 with the lower end of a bent link 60 whose upper end is pivotally connected by means of the stud-screw 61 with the forward arm 62 of the presser-bar lifting lever fulcrumed upon the bracket-arm 3 by means of the stud-bolt 63 and having a rearwardly extending arm 64: formed with an aperture 65 at its extremity to receive an actuating treadle connection. The lever-arm 62 is formed at its forward extremity with a lateral lip 62* for engagement with a roller 66 mounted upon a stud 67 carried by a block 68 fixed upon the upper end of the presser-bar G9 to which the presser-foot 70 is secured. v

The rearwardly extending arm 27 of the take-up lever is formed with a lateral boss 27* sustaining the stud-screw 71 upon which is mounted the grooved pull-off threadwheel 72 embraced by the cylindrical guard 73. The head f of the bracket-arm has journaled therein the reciprocating awl-bar 74 carrying the awl 75 disposed in alinen e-nt with the needle 9, and adjacent the awlbar is the depending stud 76 having a laterally extending portion 77 into which is tapped the screw-stud 78 sustaining the guide-roller 7 9 embraced by the thread-shield 80. Surrounding the member 77 of the stud 76 is a spring 81 having one arm 82 resting upon the lower face of the head a of the bracketarm and the other arm 83 resting upon the lug 84 at the forward end of the threadbrake lever 40, whereby the latter is pressed upward and its thread-wheel a5 is pressed normally against the operative edge 46 of the stationary thread-brake member. The lever 40 has a lateral stud 85 intermediate the thread-wheel 42 and its supporting shaft 31 around which the thread is led from the inner thread-wheel 3% of the take-up lever to the movable thread-brake member i5. The hub portion of the lever 40 has secured thereto by means of the screw 86 a stoparm 87 having a forwardly extending operative portion 88 adapted to engage the lower end of the bracket-arm head 4 to limit the upward movement of the arm 40 under the action of its spring 81 when the threadbrake member 47 is retracted from operative position by tilting the presser-foot lifting lever 62, 64.

The thread-brake plate at? is formed adjacent its thread-engaging portion as with an upwardly extending ear 47* in which is se cured the transversely apertured tension pin 89 carrying the loosely mounted tensiondisks 90 normally pressed together by means of the spring 91 embracing said pin and confined between the outer tension-disk and the slotted lower portion of a depending pressure-plate 92 secured by means of the screw 93 upon an arm 9a fixed upon the rock-shaft 95 journaled in the bracket-arm head. The rock-shaft 95 has fixed upon its forward end the crank-arm 96 pivotally connected by means of the pin 97 with the eccentric-rod 98 whose strap 99 embraces the actuating eccentric 100 fixed upon the shaft 5. The oscillation of the rock-shaft 95 derived from the eccentric 100 in each rotation of th main-shaft 5 imparts to the pressure-plate 92 vibratory movements for the alternate compression and release of the tensionspring 91 to eifect respectively the closing and opening of the tension 90.

In threading the machine the needlethread a is led from the source of supply through the usual wax-pot and thence beneath the pull-off roller 72, through the aperture of the tensionpin 89 and between the disks 90 from which it is led around the brake-wheel r5, beneath the stud 85, over the take-up thread-wheel 34:, under the thread-wheel 1-2 and over the take-up thread-wheel 35 from which it is led downwardly over the guide-wheel 7:) to the thread-arm 10. Preparatory to a stitching, operation, the take-up is raised, the threadbrake is closed under the action of the spring 81, and the needle and awl are in their retracted positions. When the machine is set in motion, the take-up arm 28 con'unenccs its descent to give up slack and the needle seizes a loop of upper thread which is presented to and entered by the beak oi the shuttle by which it is distended, thereby taking up the slack previously provided therefor by the pull-off arm 27. Just before the shuttle reaches its extreme loopdistending position, the previously opened tension 90 closes to produce a slight drag upon the thread so as to prevent overdrawing the length required for the stitch. As the take-up lever approaches its extreme thread-slackening position, the shoulder 37 engages the pin 38 and depresses the thread-- brake lever 10 to retract the thread-wheel 4-5 from opeii'ative relation with the stationary thread-brake member is whereby the resistance upon the thread is entirely removed to enable the slmttle to expand the upperthread loop freely until it is subjected to the slight drag; thereon subsequently imposed by the tension 90 as before described. As soon as the imper-thread loop has become fully distended and cast oil by the shuttle, the take-up begins to rise, thereby disengaging the shoulder 37 from the pin 38 and permitting the thread-brake lever 4:0 to regain operative relation with the member ell) under the action of the spring 81. As the takeup lever contii'lues to rise, it at first rapidly draws up the now slack needle-thread in ad vauce oi the thread-brake while the pull-oil member 72 draws thread for the next stitch from the source ()Iil supply. In its approach to extreme stitch-setting position, the take up lever is greatly retarded, so as to avoid the sudden imposition of the maximum strain upon the thread, and thereby reduces to a minin'iuln the liability to breakage at this final stage of the stitdu-produein; cycle.

From the foregoing description, it is evident that the specific form and arrangement of the takeun lever and its actuating r echanism and the thread-brake with its opera-- tive means may be materially modified without departure from the scope of the present invention.

Having thus set forth the nature of the invention, what I claim herein is 1. in a sewing machine, the combination with a needle and a cooperating loop-taker, of a vibratory take-up lever, a rocklcver, a fixed fulcrum upon which said rockde'ver is mounted, means for imparting operative movementsto said rock-lever, and a link having pivotal connections with said levers adapted for movement into substantial. alinement with said fulcrum as the take-up lever assumes its upper stitch-setting position.

In a sewing machine, the combination with a needle and a cooperating loop-taker, of a vibratory take-up lever provided with a plurality of thread-engaging members spaced apart lengthwise of said lever, a iiulerum for said lever, actuating means for said take-up lever, a thread-brake comprising a movable member and a normally stationary member cooperating therewith, arock-lever flllOt'llHlQtl concentrically with and movable independently of the take-up lever and carrying the movable member of said thread-brake and also a tlireacbengaging member cooperating with those of the take-up lever in drawing, up the thread, and means connected with said take-up lever for tilting the rocklever to render the threadbrake ineitl'ective when the take-up lever ap proaches extreme retracted position.

3. In a sewing machine, the combination with a needle and a cooperating l0op-taker, of a vibratory take-up lever, actuating means there'lor, a normally closed thread-brake comp 'ising a movable member and a normal y tationary member cooperating therewith, a rock-levcr carrying the movable member of the thread-brake, means connected with the take-up lever for tilting said rock-lever to retract its respective thread brake member from operative position, and means independent of said threadbrake member whereby the normally station ary thread-brake member may be retracted from operative position while the other member is in operative position.

4-. In a sewing machine, the combimition with a needle and a cooperating loop-taker, of a vibratory take-up lever, actuating means therefor, a normally closed threadbrake comprising a movable member and a normally stationary member cooperating therewith, a rock-lever carrying the movable member of the tlneaddn'ake, means connected with the take-up lever for tilting said rock-lever to retract its respective threadbrakc member from operative position, and means connected with the normally stationary thread-brake member for retracting the same from operative relation with the other thread-brake member.

In a sewii'ig machine, the combination with a needle and a cooperating loop-taker, oi a vibrz'ltory take-up lever, actuating means therefor, a normally closed threadbrake comprising a movable meu'iber and a normally stationary member cooperating tl'lerewith, a. rock-lever earring the movable member of the thread-brake, means connected with the takeaip lever for tilting said rock-lever to retract its respective thread-brake member from operative position, means including a normally straightened toggle device for retaining the 'normally stationary member in operative position, and means for bending said toggle device to retract said stationary thread-brake member from operative position.

6. In a sewing machine, the combination with aneedle and a cooperative loop-taker, of a vibratory take-up lever, actuating means therefor, a normally closed threadbrake comprsing relatively movable operating members, a rock-lever carrying one of said thread-brake members, a fulcrum upon which the other thread-brake member is mounted to oscillate, means connected with the takeup lever for tilting said rock-lever to retract the first named member from operative relation with the other, and means independent of the take-up lever and including a crank and a toggle device whereby the second-named member may be rocked upon its fulcrum to retract it from operative relation with the first-named member.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

OTIS E. BROXVN.

Witnesses HENRY J, MILLER, HENRY A. KQRNEMANN, J r.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Eatents, Washington, D. G. 

